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Subsection M261En
Markleeville

This subsection comprises the mountainous terrain just east of the crest of the Sierra Nevada, from the south end of the Carson Range southeastward to the West Walker River near Antelope Peak.  It has a cold and subhumid climate.  MLRA 22e.

Lithology and Stratigraphy.   Mesozoic granitic and post-batholith volcanic rocks predominate in this subsection; pre-batholith rocks are sparse.  The volcanic rocks are mostly Pliocene andesite and lahars.  The pre-batholith rocks are mostly undifferentiated metamorphic rocks.  There are small areas of Pleistocene glacial till and outwash and Quaternary alluvium.

Geomorphology.   This subsection is characterized by steep to very steep mountains.  Glacial erosion has modified much of the subsection.  Cirques, aretes, cols, and horns are common.  The rivers flow through both very steep sided V-shaped canyons and U-shaped canyons.  Alluvial basin floors are more extensive in the U-shaped canyons.  The elevation ranges from about 6000 to 9000 feet, but  up to 10023 on Hawkins Peak and 10,241 feet on Antelope Peak.  Mass wasting and fluvial erosion are the main geomorphic processes.  Pleistocene glaciation greatly modified the landscape.

Soils.  The soils are mostly Andic Xerumbrepts, Ultic Haploxeralfs, Lithic Ultic Argixerolls, and Andic Xerochrepts, plus shallow Typic Xeropsamments on granitic rocks.  Soils at the higher elevations are mostly Lithic and Andic Cryumbrepts, plus shallow Typic Cryopsamments on granitic rocks.  The soils are mostly well drained.  Soil temperature regimes are mostly frigid, but some are cryic.  Soil moisture regimes are mostly xeric.  Soils have udic moisture regimes where snow persists through spring, melting to keep soils moist through much of the summer.   Soils with aquic moisture regimes are present in glaciated terrain and small valleys,  but they are not extensive.

Vegetation.   The predominant natural plant communities are Jeffrey pine series, White fir series, Mixed subalpine forest series, and Red fir series. Lodgepole pine series occurs on some wet soils, and on drier soils where cold air drainage and frost limit the regeneration of other conifers.  Singleleaf pinyon, Utah juniper, and Big sagebrush series prevail at lower elevations.  Aspen series is common where drifted snow accumulates and provides water during summer.  Sedge meadow communities are not extensive.

Climate.  The mean annual precipitation is about 35 to 45 inches; most of it falls as snow.  Mean annual temperature is about 35° to 45° F.  The mean freeze-free period is in the range from  25 to 75 days.

Surface Water.  Runoff is rapid from most of the area.  It flows to the Carson or Walker Rivers.  Maximum flow in these rivers is during spring when snow is melting rapidly.  There are many small natural lakes or ponds in glaciated terrain. 


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